1. Field of the Invention
The present invention relates generally to musical instruments of the type that utilize vibrating strings to produce sounds. More particularly, the invention relates to an instrument in which the strings of such a musical instrument can be tuned in a predetermined temperament to produce a musical sound.
2. Description of the Prior Art
Since the dawn of history, many civilizations have adopted and used a series of musical intervals to define a musical scale. The musical scale is comprised of musical intervals between a successive pair of fundamental frequencies. Each fundamental frequency is accompanied by many harmonic frequencies. The musical interval (I) is defined, in equal temperament music, as being one-twelfth of the natural log of 2, i.e., I=ln 2/12. The piano is tuned in equal temperament. Other proportional musical intervals between successive fundamental frequencies do exist. Indian music, for example, often uses an interval of one twenty-forth of the natural natural log of 2, i.e., I=ln 2/24.
Be it Greek, Indian or modern western music, all civilizations have agreed that a multiple between two fundamental frequencies of 2 or 3/2 is pleasing to the ear. The musical intervals corresponding thereto are ln 2 and (ln 3-ln 2), the latter interval being called a fifth. It is from these musical intervals, and some others, that Pythagoras developed a musical scale.
None of the twelve successive notes of a diatonic scale, another relatively modern scale, are equally spaced between the preceding and succeeding note on the musical scale. In playing the diatonic scale, the ratios involved are simpler than those of the Pythagorian scale but nonetheless remain irregular. Since the time of Pythagoras much work has gone into developing the scale in order to include additional notes. The modern equal temperament musical scale therefore includes twelve notes as in the diatonic scale. In the modern scale there are twelve notes from the first note to its reappearance, defining an octave.
In an attempt to closely approximate the notes of a diatonic scale, the equal temperament scale for piano tuning and playing has exactly a one-twelfth difference between each succeeding note in the scale. The relatively recent development of even or equal temperament tuning has greatly simplified matters in modern music, but, due to difficulties in retuning, has lost to us many of the pleasant melodies and harmonies that existed in older music, particularly music of the type played on such instruments as the harpsichord, lyre and lute. A stringed instrument that can be easily tuned to different temperaments is not presently available.
Heretofore, a musical instrument combining the method of play and range of the piano with the capability of the guitar to extend the tonal range of a given string by the use of frets, has not been known. Relatively large stringed instruments, such as shown in U.S. Pat. No. 4,249,449 to R. Armstrong, are known. Armstrong's instrument is a musical instrument adapted for play by more than one person at a time. The musical instrument is playable by hands, picks or hammer-like devices. The use of the fingers to strike the strings is not specifically shown in Armstrong. Frets are shown in combination with the strings. The strings extend radially away from each other begining from a central open area to the outer edge of the instrument so that a number of persons can play the instrument simultaneously.
A stringed musical instrument played like a guitar, but without a sound box is formed from a piece of wood and a few strings and is known as a "stick". The "stick" is played by depressing a string into contact with a fret, much in the manner of a guitar. A "stick" is described in U.S. Pat. No. 3,833,751 to Chapman, wherein each of nine strings is tuned in a specific way, some strings being tuned relative to certain other strings.
A foot operated musical instrument is shown in U.S. Pat. No. 4,024,787 to H. Larson. Larson describes the placement of the strings in contact with the frets as a way of actually playing the instrument. The strings are therefore not plucked but rather depressed by a foot of the musician into contact with laterally extending frets. Conventional magnetic pickup means sense vibrations of the string and convert them into electrical signals which are in turn fed to an amplifier.
U.S. Pat. No. 2,906,158 to J. McBride shows a stringed instrument of the percussion type wherein a plurality of laterally extending frets are upwardly moveable in so as to strike all longitudinally extending strings simultaneously. A keyboard instrument which simulates many of the sound characteristics of the electric guitar is shown in U.S. Pat. No. 4,156,380 to T. Fulton.